Conventional vehicle transmissions have a number of vents in the transmission housing to improve cooling during operation. These vents are designed to allow air to pass through the transmission without allowing oil to leak out. Oil is recycled within the transmission and acts as a lubricant and cooling agent during transmission operation. After so many miles of operation the oil may need to be replaced in an ordinary repair or service application. An existing vent can be used as an access point in the transmission housing to enable refill of oil. It would be beneficial to have a service vent fitting that enables ventilation of the transmission during fill.
Therefore, it is desirable to enable a service vent fitting to release air from the transmission housing while fluid is being added to the transmission.